Big Bird finds that it's not easy being big -- he's too big to swing on a tire swing, to ride a tricycle, or to hide in a game of hide-and-seek.

But Elmo knows that it's not easy being small -- he's too small to cross a river, or throw a football.

At this point, the book veers from a direct narrative and becomes a general discussion of big and small. Elmo is small, Baby Natasha is smaller, Slimey is the smallest, and the Twiddlebugs are teeny-tiny, and so on.

At the end of the book, Big Bird and Elmo conclude, "Sometimes it's easy being big. Sometimes it's easy being small. That's all." No empirical evidence is presented to support this conclusion.